1. Field of the Invention
The present invention relates to a washing machine, and more particularly to a washing machine in which cleansing water pumped by a rotating blade is sprayed upon laundry with a strong pressure within an inner tub of the washing machine when a low water-level washing operation is executed.
2. Description of the Prior An
FIGS. 1 and 2 are sectional views showing an internal structure of a conventional washing machine disclosed in Japanese Utility Model Laid-Open Publication No. sho 56-108874,when respectively viewed from different sides.
As illustrated in the drawings, the conventional washing machine is provided with a cylindrical inner tub 2 having a plurality of drain holes 5 in the surface thereof to perform washing and drying operations therein, and an outer tub (not shown).
A rotating blade 4 driven to be forwardly and backwardly rotating for a regular period by a washer driving unit (not shown) is installed at the inner center of the bottom surface of inner tub 2.
A water-supply hose (not shown) for supplying cleansing water W into the inner tub 2 and a water-exhaust hose (not shown) for discharging cleansing water W in accordance with a control signal from a microcomputer (not shown) are installed on the upper side and lower side of a main body of the washing machine.
A plurality of circulating waterway casings 6 extending between the center and upper portions of a sidewall of the inner tub 2 disposed along the lower and side walls of the inner tub 2 are installed around the rotating blade 4 spaced apart from one another by a predetermined distance.
A water passage 6a is formed between the inner tub 2 and the plurality of waterway casings 6, which passage 6a is communicated with a plurality of upper discharge holes 7 in the periphery of a balance rim 9 provided on the upper portion of the sidewall of the washing machine and with central discharge holes 8 in the sidewall of the washing machine, so that cleansing water W pumped by the rotation of the rotating blade 4 is circulated during the washing operation.
A thread net 10 is provided at an upper portion of one circulating waterway casing 6 to gather waste thread or nap in cleansing water W pumped by the rotating blade 4 to be led to the upper portion via the inside of circulating waterway casing 6.
In the conventional washing machine constructed as above, a water stream is formed by a pumping force produced by the rotation of blade 4, and cleansing water W flows fluctuatingly along waterway passage 6a to be ejected into inner tub 2 via upper discharge holes 7 and central discharge holes 8, thereby performing the washing operation.
However, in the washing machine according to the conventional technique as described above, the central discharge holes 8 and the upper discharge holes 7 for ejecting pumped cleansing water W are positioned at the center of the inner sidewall or at the upper end of inner tub 2, so that the spray of cleansing water W via upper discharge holes 7 and central discharge holes 8 is rarely effective during the washing operation when the amount of the laundry is so small as to warrant a lower water level of the cleansing water W.
In other words, when the washing is performed with the low water level, the laundry cannot be agitated by being applied with a pulsation to enhance the washing effect when cleansing water W is ejected via upper discharge holes 7 and central discharge holes 8 disposed at the relatively high positions, thereby lengthening the washing time and degrading the efficiency of washing.
Also, the cleansing water W discharged from discharge holes 7 and 8 in the higher locations is not sufficient to dissolve detergent remaining around the rotating blade 4. Thus, the washing is insufficiently carried out, and undissolved detergent may be left even after finishing the drying cycle.